AUCKLAND, NEW ZEALAND - JANUARY 02: Naomi Osaka of Japan plays a forehand in her match against Annika Beck of Germany on day one of the ASB Classic on January 2, 2017 in Auckland, New Zealand. (Photo by Anthony Au-Yeung/Getty Images)

Osaka currently holds the No. 29 spot among the 100 highest-paid athletes in the world, while Williams is right behind her at No. 33. This year marks the first time since 2016 that two women have ranked among the top 100 highest-paid athletes.